摘要:

THE ANALYST. MARCH, 1889. PEPPER ANALYSIS AND THE OCCURRENCE OF PIPERIDINE THEREIN. BY WILLIAM JOHNSTONE, PH.D., F.I.C., F.C.S,, ETC. (Bead at Meeting, January, 1889.) Mr. PRESSDENT AND GENTLEMEN, The subject of the paper I have the honour of reading before you this evening ie ‘ Pepper Analysis and the Occurrence of Piperidhe therein.” What iE; known as black pepper is the dried immatured fruit of Piper Nigmm, belonging to the Natural Order Piperacm . The shrub or plant is a native of tropical regions, and is cultivated in various parts of the Indian Archipelago and in the West India, and that imported into this clountry comes principally from the Islands of Maltma, Java, Borneo, and Sumatra.42 THE ANALYST. The plants of the order of Piperaceae contain an acid resin, a volatile oil, a volatile alkaloid, and a crystalline substance called piperine. They possess pungent aromatic, astringent, and narcotic properties.Perennial, Stem.-Its stem is 8 to 12 ft. long, trailing or climbing, shrubby, flexuose, and dichotomously branched, jointed, swelling a t the joints and often throwing out radicles there, which adhere to bodies like the roots of ivy, or become roots, striking into the ground. Leaves.-B’rom 4 to 5 in. long, alternate, distichous, broadly ovate, acuminated, of a full green and glossy colour, paler beneath, five to seven-nerved, the nerves connected by lemer transverse ones or veins, and prominent beneath. In~orescence.-~pikes opposite the leaves, chiefly near the upper ends of the branches; shortly stalked, pendulous, 3 to 6 in.long ; petioles rounded, from jj to nearly 1 in. long. Flowers unisexual or hermaphrodite, small, whitish. Fruit.-Distinct, braccate, ripening irregularly all the year round, about the size of a pea, at first green, then red, afterwards black, covered with pulp. The black pepper of commerce consists of the entire berries, with the pulp adhering, gathered before they are quite ripe and dried in the sun. The commercial varieties are at least ten in number, viz., Acheen, Alleppy, Kampoot, Lampong, Penang, Siam, Bingapore, Tellicherry, Trang, and Long pepper, the names indicating the localities from whence they are obtained. Blyth remarks that the differences which these different varieties of pepper present to the eye are evident enough when the several samples are at hand for corn- parison,” a statement I by no means agree with, (( but it takes a very practised observer to identify a solitary sample j and if samples of each of the kinds were mixed together, it is doubtful whether an adept even could separate the berries again, identifying each sort with any correctness.” The merchant, however, relies more upon the weight than the appearance.Taking a handful of peppercorns, he can tell in a Tmoment whether it is a light o t a heavy ample, and thereby judges the quality of the pepper. That there is a difference in the weight of the various varieties of the different peppercorns is evident from the results obtained by the author, who carefully three times weighed 100 berries of each kind, which gave the following average results :-- Average of Three Weighings of 100 Peppercorns.Acheen .. .. .. 5.1976 grms. .. . . .. 3.8438 ,, .. .. .. 4.4540 ,, Kampoot Lampong . , .. .. 3.5410 ,, Penang .. .. .. 3.9028 ,, Siam .. .. .. 4.27’76 ,, Singapore . . .. . . 4.5338 ,, Tellicherry . . . . .. 4.4421 ,, Trang .. .. . . 4.8101 ,, Penang, white .. . . . . 4,9360 ,, Shm, 9 , .. . . . . 501441 ,, Singapore 99 . . . . . . 4.6936 ,, Botany. Very doubtful, I should say, indeed. AllePPY The pepper of commerce, whole or ground, is therefore a mixture of the different kinds of peppers, and is a condiment which has had a good deal of atfention paid itTHE ANALYST. 43 lately, owing to some successful prosecutions which took place at Liverpool some time ago, when a large quantity of ground pepper was condemned as being adulterated with a material known by the name of Poiverette, a hard, tasteless, woody substance, abso- lutely worthless as a condiment, impwted expressly into this country from Italy, for no other purpose than of fraudulently increasing the weight of ground pepper.Xt was not, however, wholly owing to the addition of Poiverette to pepper that I was induced to undertake the following analysis, although it tended greatly in that direction, but to the great divergency of opinion that seemed to exist amongst various authorities as to the amount of piperine contained in pepper. The standard works of reference are also at variance with one another, Watts’ Dictionary stating that Penang white pepper gave a mean of 5 24 per cent. and Singapore white 9.15 per cent., whilst Singapore black gave a mean of ’7.15 per cent.; Sumatra 8-10 per cent. Mr. Heich (ANALYST, vol. xi., p. lSS), from 5 to 9 per cent., Mr. Winter Blyth, from 1.8 to 5.5 per cent., Dr. Muter in his ‘‘ Organic Materia Medica ” (third edition), from 2 to 3 per cent., and Ure’s Dictionary (sixth edition) a fraction of a grain, and lastly, Dr. Stevenson, in the ANALYST, vol. xu., p. 141, from 6.62 to 7.14 for black pepper, and 6.47 per cent. for white pepper. Owing, therefore, to such conflicting evidence, with considerable variation in the amount of piperine said to be contained in similar peppers, I: determined to investigate the subject myself. I have done so, and the results obtained in that investigation furnish me with the contents of this paper, and although I have not been able to reduce the limits of variation (but on the other hand to increase them), I have been rewarded by the discovery of the fact that pepper contains a volatile alkaloid, and I have every reason to believe that it is piperidine, from the results I hav6 obtained upon the analysis of its platinum salt :- Found.Calculated. C . . .. . . 120.0 20.02 20.60 H . . .. .. 24.0 4.32 4.15 N . I .. . . 28.0 5.01 4-80 Pt . . . . .. 197.4 33.93 33.89 c1 .. .. . . 213 0 36-63 36.56 -- 2(C,H,,N. HC 1) Pt CI, .. 582.4 99.90 100~00 In entering upon this investigation I had in the first place to obtain genuine speci- mens of pepper, and through the kindness of my friend Mr. Worcester, I obtained from Nessrs. Lewis and Peat, well-known brokers in the City, thirteen specimens, and I now take this opportunity of thanking them for their liberality and the trouble they took to obtain them for me.The samples as received by me were taken from the bulk, that is, dock or cargo sample3, and are therefore undoubtedly genuine, and are repreEentative samples of the pepper which is sent to this country, having undergone no particular process of cleaning other than having simply been screened by means of a sieve, containing seven meshes to the inch, before being ground. Having obtained such magnificent samples, my next consideration was the adoption of a proceEs for the estimation of the piperine, which would give constant and accurate44 THE ANALYST. results, as I had grave doubts as to the accuracy of the alcohol method usually followed, that is, extracting with alcohol and then purifying by potash, and subsequently again crystallising from alcohol.At this point I therefore directed my attention to the old but well-known fact, that piperine, when treated with caustic potash and alcohol, splits up into piperidine and pipric acid, as represented by the following equation :- C17H,,N0, + KHO = KC, PHQO, + C,H,,N CI7H,,NO, + HZO = C,?H,,-,O, + C,H,,N Piperidine, as yon are all well aware, is a volatile alkaloid possessing strong alka- line properties (B.P. 106" C.), so the idea immediately occurred to me that if the above equation could be made to work in practice so as to yield the theoretical quantity of piperidine, the difficulty would be solved, there being no difficulty experienced in distill- ing off the piperidine and titurating the distillate with standard acid.The next thing, therefore, was to prove the above reaction, so having some very fine crystals of piperine in my possession, which I had obtained from Messrs. Macfttrlan and Go., of Edinburgh, some years ago, and which I had every reason to believe were pure, but erring on the safe side I re-crystallised them, and subjected various quantities to the action of caustic potash and alcohol. A series of misfortunes and unsatisfactory results followed, so unsatisfactory that I got quite disheartened, concluded that it was a miserable failure, and allowed the subject to remain at rest for over eighteen months, when fortunately one idle day I again returned to the subject with increased vigour.The trouble I had to encounter before was the difficulty of keeping the stoppers of the bottles tight when subjected to heat and pressure, as the digestion was carried on in the water-bath at a temperature of looo C. If one was fortunats enough to get them to remain tight under pressure it was 100 to 1 that when allowed to cool, and you attempted to remove the stopper, it would be found hard and fast, no alternative being left but t o knock off the neck; otherwise, if it was got out without breaking the bottle, I always found a great loss. After a dozen bottles had been used up in this manner, not counting the ones that burst, I found that in three instances I had obtained practically theoretical results (which will be seen by referring to the three first estimations in the accompanying table), so encouraged by my results, and a t the same time deterinined to overcome the difficulty, if possible, and make the process a working success, I designed the following little arrangement., with which I have obtained actually theoretical results, which I: have tabulated in the diagram before you, the first three estimations, as already stated, having been made in an ordinary stoppered bottle. PIPERINE.Taken. Found. %400 -83075 -2520 .24937 -5900 -58450 04320 *43170 -7640 ~76380 -5288 -52212 *3530 -35197 1.0108 1.01052 Per Cent. 98.89 98-95 99-06 99.93 99.97 99.85 99.70 99.97THE ANALYST. 43 This instrument, as you will observe, consists merely of an or- dinary 4-oz. bottle with its mouth ground flat, and is simply closed by placing a circular piece of sheet india-rubber over it, and then placing it in its holder, putting the clamp in position, and finally making it perfectly tight by screwing down the two screws made for the purpose, put into tho water-oven, digested at a temperature of loo@ C.for from four to six hours, when the reaction is complete, then removed from the oven and allowed to cool. When cool it will be found that the bottle has remained perfectly tight, none of the contents having escaped, so all that now remains to be done is to unscrew the clamp, and transfer the contents of digestion bottle to a distilling flask fitted with a condenser, and distil the piperidine and titurate the distillate with standard acid. Having, therefore, satisfied myself of the accuracy and adaptability of the process, the next thought occurred to me to try the estimation of the piperine contained in the pepper direct, that is, digesting the ground pepper with caustic potash and alcohol for six hours, and then distilling as before.Ten grms. of ground pepper was carefully transferred to the digestion bottle, 30 C.C. of alcohol added, and then about 3 grms. of caustic potash dissolved in 25 C.C. of water also added, the indiarubbzr placed in position and the clamp screwed down, and then digested for six hours, allowed to cool, opened at convenience, and contents of the bottle washed into large flask with plenty of water, distillation commenced and carried on until the distillate coming over is neutral, aliquot portions of which are then titurated with 10 ~ using methyl orange as an indicator.H,SO, Several experiments were performed in this manner on one sample of pepper, con- cordant results being obtained in every instance, which established the reliability of the process; consequontlg all the samples of pepper were treated in this manner, and tho results so obtained are tabulated in the table before you. The piperine estimations having proved successful, I decided to make a complete analysis of the various samples, the results of which I have the pleasure of laying before you this evening. I will now, therefore, describe in detail the processes employed by me so as t o obtain thefigures I have placed upon the diagram. Jfoisture.-The moisture is estimated by the ordinary method of drying a weighed portion of the ground pepper in a platinum capsule at looQ C.in the water-oven until the weight remains constant, and then noting the loss in weight. Oil.-The volatile oil is estimated by distilling 20 grms. of the ground pepper with water in a large flask, shaking the distillate several times with ether, and evaporating the separated ether in a weighed flask at a very low temperataure, and finally drying over sulphuric acid. Piperidine.-Twenty grms, of the ground pepper are distilled with water in a similar manner as that for the oil estimation until the distillate is neutral (450 C.C. being about the quantity necessary to distil). An aliquot portion is then titurated with -- N 10- using methyl orange as an indicator. I n the piperidine estimation it occurred to me that the process of distilling with water might be done away with, and the pepper HW446 THE ANALYST.put into a boat and then into a hot-air tube, heated to 230 to 240° F., aconstant current of air being aspirated through it all the while, the air ultimately passing through a bulb of rstandard acid. Working in this manner, and after an hour's treatment, the acid was washed out of the bulb and its equivalent of soda added, the excess of alkali being titurated back with 10 - using methyl orange, as usual, as indicator. The results obtained by working in this manner are interesting on account of only a third of the piperidine being obtained in this way, or rather only a third of that obtained when the pepper is distilled with water.The following are the results obtained in duplicate when working in the manner just described, using 5 grms. of the pepper:-- &SO, No. Sample I. 11. IiL IV. V. VI. VIT. 0.13 0.106 0 16 0.25 0.11 0.19 0.19 0.13 0*1@5 0.12 0.25 0.10 0.20 0.17 N~.Sample VIiI. IX. X. XI. XII. XIII. XIV. 0.29 0.1'7 0.127 0 093 0.076 0.085 0.272 0.25 0.17 0.127 0.093 0.076 0.085 0.2'71 These results tend to suggest that the piperine was to some extent hydrolysed by the action of prolonged boiling with water, but such is not the case for if pure piperine is boiled with water no piperidine is obtained, and it is also disproved by the fact that there is no difficulty in getting the distillate neutral; the amount of piperidine distilled represents a mere fraction of the piperine remaining in the pepper.I am rather disposed to the theory that there may be 8 particular ferment contained in the pepper capable of producing the hydrolisis of piperine when boiled with water, or it may be due to the existence of another alkaloid more easily hydrolysed than piperine, anyhow these are the results cbtained, and any one is welcome to continue the investi- gation further if they should feel so disposed Ash.-The dried sample used for the moisture estimation is incinerated at a very low temperature, the most convenient arrangement for this work being a jar-muffle, which is infinitely superior to any kind of burner. The residue obtained is the mineral or inorganic matter, and this in turn is then treated with water and then with dilute acid, so as to obtain the portions soluble and insoluble in those menstruums, the in- soluble in acid portion, representing the proportion of sand present, and is of special importance.Piperine.-Ten grms. of ground pepper are digested in a closed bottle similar to that already described, from four to six hours, with 3 grms. of caustic potash dissolved in 35 C.C. of water and 25 C.C. of alcohol. When the digestion is finirJhed, the apparatus is allowed to cool and its contents then carefully washed into a large flask, a few pieces of tobacco-pipe stalks being also put into the flask so as to prevent the violent bumping which would otherwise occur, distillation commenced and continued until the distillate coming over no longer shows signs of alkaline reaction, which is generally the case when about 750 C.C.have passed over. The distillate is then made up to one litre, and titurated as before with 10- using methyl orange as indicator. H SSO, Ribre crude.-Between 3 to 5 grms. of the ground pepper are placed in a flask and covered with 50 C.C. of dilute sulphuric acid (5 per cent. or 60 grms. of sulphuric acidTHE ANALYST. 47 per litre), to this 150 C.C. of water are added and the liquid boiled for half an hour, the flask having previously been attached to an upright condenser. After subsidence, the supernant liquid is run off by means of a syphon into a beaker, and the residue is then twice boiled for half an hour with 200 C.C. of water. After removing as much of the clear liquid as possible, by decantation, the residue, to whichis added any sediment that may have become deposited in the beaker containing the acid extract, is next boiled in the same manner with 50 C.C. of dilute caustic potash (50 grms.of KHO in 1,000 c.c.) and 150 C.C. of water for half an hour, and after sub- sidence the supernant clear liquid is syphoned off into another beaker, and the residue isagain extracted by boiling fJwice with 200 C.C. of water. The residue obtained after the above process of extraction has been carried out, together with any sediment deposited in the beaker containing the alkaline extract, is now thrown upon a weighed filter and washed well with boiling water, alcohol and ether. The filter and residue are then dried at a temperature of 105 t o 110” C. and weighed, and then, in order to ascertain the small proportion of ash which the woody fibre contains, also the accompanying sand, the filter is ignited and the ash found deducted from the previous weight.This is merely an approximate determination, as the term crude fibve designates tothing beyond the fact that it does not consist of pure cellulose, but that a certain amount of Iigenous substances are insoluble in acid and alkaline solutions of definite strength, and alcohol and ether, after definite treatment, such as already described, fur- nishing results which are of some comparative value, but still leaves much to be desired. Nitrogen and AZbunzinoids.-The nitrogen was determined in the usual manner with soda-lime. AZcohoZic Extract.-Two grms. of the ground pepper are extracted for 24 hours with 95 per cent.alcohol. The pepper under examination is placed in a tube, which in turn is inserted in a Soxhlet’s extraction apparatus. The tubes used for this purpose are ordinary test tubes cut in two, the upper half having a piece of fine linen (previously washed and extracted) tied over the mouth end of the tube, then a wad of extracted cotton-wool of sufficient thickness is placed inside the tube, upon the linen so as to prevent any of the solid particles of the sample finding their way into the receiving flask, and then another wad of cotton-wool is packed on the top of the sample and the whole inserted in the Soxhlet apparatus, and tho extraction continued, as already stated, for 24 hours, The alcohot is then distilled off, and the flask dried in the water-oven until weight remains constant.I must here remark that it is necessary to distil the recovered alcohol with dilute sulphuric acid if it is to be again used for any other purpose, so as to get rid of the piperidine which it now contains. Starch.-Before proceeding to convert the starch into dextrine, the pepper must be carefully extracted with 95 per cent. alcohol, so as to remove substances other than starch which are acted upon by the acid, and also which have the power of reducing Fehling’s solution, such as piperine and piperidine, both substances being possessed of the power of reducing Fehling’s solution.48 THE ANALYST The residue contained in the Soxhlet tube is, therefore, readily available for this purpose, having been thoroughly exhausted with alcohol.Without drying, therefore, it is carefully washed off the cothon-wool into a suitnble flask, with about 300 C.C. water and 20 C.C. HCl (sp. gr. 1.121) added, the flask con- nected with an upright condenser and heated in the water-bath for 3 hours. After cooling, the liquid is filtered, and the filtrate very carefully neutralised with caustic soda and diluted, so as to measure 500 C.C. ; finally titurated with Fehling's solu- tion, and the results calculated to starch or any other desired basis. A few drops of chloride of zinc may be added, so as to assist clarification of the liquid before filtering. Extraction with alcohol is indispensable, without which the results are most uncer- tain and unreliable. Proper and careful extraction with uninterrupted boiling are the two most important conditions to be attended to.These results, therefore, which I have this evening placed before you, were obtained by the methods I have just described, and although individually I am disappointed with them, I must admit, nevertheless, they are of considerable value, as thay are repreeen- tative analyses of several varieties of pepper, obtained from various quarters of the globe, and as met with in commerce and as shipped to this country. The moisture and oil determinations are of no practical value, and the same may be said of the piperidine and piperine ; the piperidine being in too small quantity to be of any use, the piperine, on the other hand, exhibiting large variations, showing a maximum of 13.03 per cent., with a minimum of 5-81 per cent., and giving a mean of 8-35 per cent.The albuminoids and matter soluble in alcohol are also of little practical value (except that an excessive amount would reveal the presence of Bome foreign seed rich in nitrogen), so that we are left with the starch, fibre, and ash as the only data which approaches to anything like reliable, contant, or uniform amount. Fortunately in two of these we have very reliable data, viz., in the ash and fibre. Too great a value, in my opinion, has been placed upon the amount of starch, as will be seen in referring once more to tho diagram, a maximum of 42.45 per cent. being obtained, with a minimum of 29.60 per cent., giving a mean of 36.02 per cent. for the black peppers. It may be of more value in judging white peppers, but as I had only three samples of white, my remarks do not, therefore, apply to white pepper.An increase of fibre indicates the addition of a more fibrous material than pepper. The fibre will be observed to reach a maximum of 15 per cent., with a minimum of 10 per cent., and a mean of 12 per cent., so that we can easily accept 20 per cent. as a fair basis for calculating the amount of fibrous material. When we come to the consideration of the ash, however, we have very reliable data, the amount of ash immediately indicating the addition of any material containing a larger proportion of inorganic matter than pepper. The ash is undoubtedly a most reliable and valuable constituent, and it will be observed that not in a single instance has it reached 5 per cent.If we leave out the Long pepper, we obtain a maximum of 4.65 per cent,, with a minimum of 3.51 per cent., and which gives a mean of 3.96 per cent. Anything, therefore, above 5 per cent. must be looked upon with Euspicion. Another valuableindication is the solubility of the ashin water and in hydrochloric acid. Jn water we have a maximum solubility of 24'2 per cent., a minimum of 1.41 per cent., with a mean of 1-93 ; and the insolubility in bydrochloric acid gives a maximum OP *62 per cent., with a minimum of 0.06 per cent., and a mean of 0.82 per cent. (Long pepper gives 1-47), so that anything over 1 per cent. of insoluble matter in hydrochloric acid ought to be reported against as containing sand or clirt.I 1 Acheen .. Alleppey . . Kampoot . . Lampong .. Long Pepper . . Pcnang, W.C.. . Siam . . .. Singapora . . Ttllicherry . . Trang . . .. Penang, W. . I Siam, W. . Singapore, W . Husks, etc. . I_- doisture. 15.15 15.36 13-82 15-22 12.26 15.04 14.06 14.72 14.24 14.02 14.94 13.13 15-62 12.54 I Oil. I 1.51 1.87 1.63 1.42 1-56 0.98 1-29 0.99 1.01 1-40 0.53 1.41 1.14 1.74 0.50 0 44 0 53 0 77 0-34 0.46 0.76 0.72 0.39 0.47 0.34 0-2 1 0.42 0.74 1.06 1-34 1.42 1-82 1.51 1-72 1-57 1-40 1-40 1.49 0.90 1-37 1-61 1-47 isb. - 3.79 4.66 3-51 4.46 7.57 4.14 3.65 3.64 3.87 3.96 2.47 2.25 1-03 16.34 L7H*BN09 12.21 13.03 8.13 11-05 7.15 6-41 6-89 5-72 8.25 5 21 8-57 7.79 8.66 6-32 - -- 10.00 13-10 11 65 15.05 13.75 11.70 12.25 10.75 1PlE IOTC 4.32 4.4: 4.2( 22.H .lbumi- noids. 2.34 2-62 5-37 7.25 6-93 8.37 6 93 6 31 5 87 6.68 2.62 6 00 7 .oo 6.50 - tarch. 42 45 39.60 37-50 30.80 32.10 41.65 40-15 32.18 33.33 37-50 51-00 53-5c 52.0C 11% oluble in c,a,o. 0.84 2.12 9.5i 4-55 3.50 5.44 6-26 5-55 2.60 4.54 0.46 0.1 1 1 7 6 4.23 -_--__ Undeter- mined. 11.21 17-20 8-27 9.43 14.84 5.81 7.76 19.42 18 29 15.53 14-42 11.18 8.13 16.91 Total. 100. 1.00. 100- 100- 100- 100. 100- 100- 100. 100- 100- 100- 100. looq h’. Solutility of Ash in - H,O. - 1.41 2.72 1.50 2.15 2.1 8 1-71 1-64 2.00 2-26 1.74 0-31 l.1E 0-3( 1-1( -- HC1. - 1 -74 1-57 1.10 2-10 3.92 1-63 1.67 1.48 1-65 1-92 1.9: 0.95 0.65 6.7 1 PiO, 0-62 0.06 0.31 0.21 1.47 0.56 0.34 0-16 0.06 0-30 0.19 0.09 0.15 8.53 II_

ISSN:0003-2654    

DOI:10.1039/AN889140041c

出版商:RSC    

年代:1889

数据来源: RSC

摘要:

50 THE ANALYST. THE WESTPHAL BALANCE. BY W. F. K. STOCK, F.C.S., F.T.C. (Read at Meeting, Januavy, 1889.) IN Mr. A. H. Allen’s most valuable and painstaking paper, “On Some Abnormal Samples of Butter ” (ANALYST, January, 1889), there are some remarks on the Westphal balance which will come as a positive shock to any chemist who may have been too confiding in the performance of an untried instrument, Mr. Allen did not mention what his balance had cost, but it may safely be said that the cheaper such an instrument is, the more likely will it be to possess defects, for the reason that the actual value of the material used in its construction is as nothing to che labour-cost of its truthful graduation and the accurate adjustment of its weights. The ease and rapidity with which the densities of liquids can be ascertained at any temperature between 0” and 99.5” C.by the use of the Westphal balance give it a place in the laboratory which nothing else could well supply, and I should very much regret if analysts, and especially the members of this Association, should find it necessary to give the cold shoulder to this handy little machine, for which reason I should like to say a word in its favour. I cannot do this batter than by giving my own experience of it. It has a set of “rider ” weights in duplicate. Before taking it into work, I made a rigid inquiry into its performance, thus : The graduations on the beam were measured up by means of a fine springbow divider worked with a screw ; the spaces were taken off with a scale of equal parts (by Archbutt) and found to be accurate.The displacement of the plummet in distilled water at 1 5 . 5 O C. was got on a short-beam balance by Bunge, and the whole of the rider weights were weighed on the same balance, with the beam oscillating, by which means a degree of accuracy beyond the fourth place of decimals was reached. The balance I use was supplied by Oertling, at a cost of three guineas. The following table shows the variations in the riders :- Number of Weight. 1 l a 2 aa 3 3a 4 4a Weight in Grammes in Air. 6.4806 6.4796 ,6482 06483 *0655 *0655 *0070 -00’7 1 Relation to Unity. Plummet displacement = 6.48 grms. 1 *00007 -99992 10003 *10004 ~01010 *01010 *00108 *00100 Density of rectified spirit by Westphal . . . . -8383 7) 9 , ,, Bottle .. .. -8385 A glance at the third column of the table will tihow that the maximum deviation from unity is 1 in the fourth place of decimals, a result which is creditable to the maker, since the balance was supplied in the ordinary way, without any attempt at selection.THE ANALYST.51 The simple law which governs the action of all balances of the Steelyard type tends to aggravate error in direct proportion to the increase of mass in the weight, and the use of rider weights for accurate work on chemical balances lies within very narrow limits, nothing beyond a centigramme being common. In the Westphal balance, how- ever, the whole displacement, which may amount to 10 grms. or more, is called unity, and therefore, unless very palpable imperfections are present, they do not practically vitiate the results; and seeing what can be had at a moderate cost, as in the case of my own purchase, I think there can be no doubt that if another guinea were added to the price, and the extra cost were devoted entirely to the correction of spacing and adjustment of weights, a reliable and trust worthy instrument would be the outcome.The maker could then afford to issue a guarantee with each instrument. DISCUSSION. Mr. ALLEN said the instrument which he had referred to in his paper on “ Some Abnormal Samples of Butter ” was a Westphal balance, obtained from Messrs. Becker and Co., of Maiden Lane, and, he believed, cost 28s. I t was of the ordinary kind sold by that firm. The fault was simply in the inaccurate division of the beam at the eighth point.I n other respects it was a perfectly Satisfactory instrument, and he had used it for a considerable time with every satisfscbion. It must be remembered also that the gravities commencing with the figure 8 were all comparable among themselvee, and it was only when i t was desired to compare densities obtained by that instrument with those determined by the specific gravity bottle that any discrepancy became important. Still, he had thought it his duty to mention the matter, as he falt that his brother analysts were very probably recording figures in which the same error was involved. He had recently obtained a highly satisfactory Westphal balance from Sartorius, at aE2 lOs., and also one from Oertling, at E3 3s. Both of these were admirable instru- ments, and in the case of Oertling’s instrument the bearings were of agate, but in both balances the knife edges were of steel. He rather preferred Oertling’s balance, as it was intended for use with tt 5 C.C. plummet instead of a 10 C.C. plummet, which latter was supplied with the Sartorius instrument. (Conclusion qj Society’s Proceedings.)

ISSN:0003-2654    

DOI:10.1039/AN8891400050

出版商:RSC    

年代:1889

数据来源: RSC

摘要:

THE ANALYST. 51 ABNORMAL BUTTERS FROM. IRELAND, DENMARK, AND SWEDEN. BY CEARLE~ ESTCOURT, F.I.C., F.C.S. IN April, 1885, a client of mine delivered a sample of Irish butter, duly sealed, and laballed as having bsen purchased under the Food and Drugs Act. The Public Analyst for the Borough where the sample was purchased, had con- demned it as being a mixture of foreign fat, and my analysis confirmed this result. SO-CALLED IRISH BUTTER. Specific Gravity at 210° F. Insoluble Fatty Acid. 865.1 92.07 The Analyst for the Borough had condemned this upon the result by Reichart. Upon investigating the matter I found that my client had purchased this butter from a very large firm in Ireland, who were, he said above suspicion, one of the firm, indeed, was a member of Parliament,52 THE ANALYST.Certificates for the butter in question had been givan by two of bhe first chemists in Dublin, and it was said even to have passed Somerset House. When the case came before the magistrates however, the Irish firm did not, and my client, acting under my advice would not, ask the magistrates to send the sample to SJmerset House. With the reputation for honesty which all tha parties concerned bore, it only needed a possibility of seeing the cows milked, and a supervision of such milking by inexperienced psrsons to prove this (‘ an abnormal sample of butter.” Fortunately, however, under pressure from my client, we obtained the whole secret of the process of manufacture. Last year’s butter was purchased and wdshed free from all rancidity, churned again with skim milk, oleomargarine, and about 10 per cent.of nut oil, t h s result being a perfect butter so far as flavour was concerned. I n 1884, two samples of Danish butter were submitted t o m9 for analysis, from one of the boroughs for which 1 am analyst. I was of opinion that they were adul- terated, but before any proceedings were taken, duplicates of ths samples wero sent to Somerset House, with the result that they pronounced them pure. The following are the analyses :- Somerset House, Estcourt. No. 1, No. 2. KO. 1. No. 2. Insoluble Fatty Acid . . 89.35 88.85 89.45 88-59 Sduble Fatty Acid . . 4.18 4.24 4-20 4-01 865.70 866 0 MpecificGravitrg a t 310°F. . . .. . . Thess results would, I am convinced, be now held by all analysts, including Dr. Ball himself, sufficient proof of adulteration.The sol~ble fatty acids being lower than those even recently obtained by Mr. Allen from his abnormal butters. It will be remembered that this was before the period when analysts believed that a mixture containing any cmsidersble quantity of butter-fat would pay. It had always been supposed that adding a flavouring of butter-fat to foreign fat was the ordinary method of manufacturing butterine. I n 188.5, some clients of mine who are very large purchaeera of butter, and have special purchasing agenciss in both Denmark and Ireland, and who, I may say, are the largest retailers of butter in Great Britain, brought me a sample of a cmsignment purchased by their agent in Denmark. The following were the results of the analysis : - Dr.l3ell. Mr. A l l m . Estconrt. Specific Gravity a t 210” F. . . . . .. . . 862.50 Soluble Fatty Acids . . . . 3.48 . . 3.50 1 pronounced this to be a mixture, and both Dr. Bell and Mr. Allen agreed with me. On reporting the results to my clients, they informed me they had submitted the sample for analysis solely because their buyer had written that ‘‘ this shipment was poor in quality.” In the face even of these analyses, the producers asserted that the sample was genuine. I n August, 1888, a sample of Swedish butter was received from the butter importer Specific Gravity at 100° F. . . .. 908.42 .. .. Iusoluble Fatty Acids , . . . 9048 . . 90.1 2 Reichart 24 grammes . . . . . . 8‘3 . . in this country, by the hands of a solicitor a t Wigan.THE ANALYST.53 ~~ This sample was duly sealed, labelled, and numbered 402 by the Inspector of the The analyst for Wigan found that the sample was a mixture, and, on analysis, I When the case came into court, the butter importer asked for the On analysis by Dr. Bell and his colleagues, they agreed with us in pronouncing the The following are the results of analysis :- Corporation of Wigan. agreed with him. sample to be sent t o Somerset House, and this was accordingly done. sample a mixture. Somerset House. Estcourt. Wigan analyst Specific gravity at 100" F. . . 909.4 .. has- been re- quested to give not done so. 9 , ,, 212* E'. . . . . 865.5 results but has Insoluble fatty acid . . 90.0 89 *8 Soluble ,, . . 3.33 3.40 Shortly afterwards two more samples, G, N, were delivered to me by the same butter importer, and I found on analysis the following results :- G.N. Specific gravity a t 2 1 2 O .. . . 864.5 864 *O Insoluble fatty acid . . .. 89.7 89.0 Soluble 99 . . .. 3.53 3.57 These mere reported to be from the same farm as the Wigan 402, and had been anrtlysed by Professor Stein, with the same result as 402. Later on, the gentleman who represents the Danish agricultural interests in this country, in company with the butter importer, called upon me. I explained to them my view as to the incompleteness of the test of supervision applied at the Swedish farm, whence G and N were taken, and on a suggestion of the agent that it might be essential that I myself should visit the farms, I expressed my willingness to place several days at their disposal.Having personally supervised the milking of many hundreds of cows of various dairies, I may, without egotism, say that my experience is unique as to the possibilities of fraud or error committed during such operations. Mr. Carter Bell, the analyst for Salford, and two of our Manchester food inspectors, are the only persons having to my knowledge a similar experience. Shortly after this interview, the gentleman representing the Danish agricultural in- terests wrote to the Nanchester papers explaining how carefully the supervision of the milking had been carried on, from which Professor Stein had obtained his samples G and N. In reply to this I pointed out that the supervision extended only t o the churning of milk, which itself came from no one knew where.I also stated that no genuine sample of butter from England, Scotland, Wales, and Ireland had yet been analysed giving such abnormal results. As it seemed incredible that Denmark or Sweden should possess a special breed of cows, or grow naturally special food, in my reply I placed my services for a few days at the dispoeal of the gentlemen who interviewed me, in hopes that this extraordinary mystery might be unravelled. From that time until the 3rd of January, 1889, I heard no more of this matter ; then, to my surprise, I saw in the ANALYST the paper on abnormal butters.54 THE ANALYST. From this paper, and the analysis of samples B and 0, Danish butter, it appears that we are expected to infer that the samples of Swedish butter, Nos. 402 and G and N, were similar in character to B and 0.The analyses negative this assumption at once While no one would hesitate to pronounce Nos. 403 and G and N adulterated, very few analysts would venture t o assert that 0 and B might not be abnorntal butters. The figure for soluble fatty acids is about equal to the lowest figure to be found in Dr. Bell’s book, and the specific gravities approach exceedingly near the lowest normal. The visit to Denmark has therefore not materially advanced our knowledge of the butter question. Whatever may be the opinion of analysts with regard to the proof of genuineness of B and O afforded by Mr. Allen’s paper, no one can doubt the lack of such proof to clear the Swedish samples from the character of adulterated butters. And now with regard to the title of Mr.Allen’s paper, which appears to me singularly incomplete. If in the syllabus of the meeting of the Public Analysts for December, there had been the slightest indication that the abnormal butter had been Danish or Swedish, I think it probable that very valuable information might have been obtained on this subject, as Dr. Bell, Nr. Betley, of Wigan, and myself, one or all, would in all probability have been present. And now for the main object of my paper, which is to demonstrate that butter analysis is as reliable as ever, and that so-called abnormal samples of butter have not as yet been proved t o be anything more than mixtures. One cannot help being struck by the phenomenal breed of Danish and Swedish cows, which, according to the information obtained by Mr.Allen, secrete one week perfectly good butter-fat, and without any notice, and without change of conditions, another week produce what an experience of all British butter would lead us to call a mix t u r e. I f this is possible a very serious in justice has been done to the Danish agriculturist by those who are acting in his defence. The so-called supervision of the milking a t these Danish farms was performed by gentlemen whose honour, intelligence, and high ability in the special professions to which they are devoted cannot be questioned. On the ground, however, of their entire lack of experience of the new calling which they have undertaken, I think grave objection might well be taken. There were five gentlemen to supervise the milking of sixty-five cows at B farm.Mr. Allen shows exactly the amount of supervision he, with his experience, thought necessary, when he says, the milking, etc., was conducted under the unremitting super- vision of the whole party, ‘‘ especially of Mr. McGregor and myself.” If the party of five could by any possibility have seen sixty-five cows milked without losing sight of any portion of the nailk for an instant until it was sealed up, then why is it necessary to weaken the effect by singling out as deserving of special remark, ‘‘ especially Mr. McGregor and myself ” 1 The fact is, I fear, there is not one of these gentlemen who would venture, under cross-examination in a Court of Justice, t o declare that no oily matter could possibly have been introduced in the milk.THE ANALYST.55 - This is especially the case when it is remembered that a very small quantity would if added to the milk make a 20 per cent. adulteration OF the butter, indeed one part to 170 parts of milk would suffice. Then, again, the milk should have been creamed at once by the ordinary separator, so that churning could have taken place without leaving the milk all night, which was dangerous, even though it was sealed up. Surely it cannot ba alleged that in such well-regulated dairies this apparatus is not known. From the foregoing remarks it will be evident that fraud might have been com- mitted. I do say, however, that the agent of the Danish Agriculturists in England has done the farmer a serious injustice in not com- pletely proving the impossibility of fraud.This is, indeed, very necessary when it is remembered that nearly all the mixtures which hava been condemned in this country have baen alleged to be Dmish or Swedish, and I trust the Local Government Board or the Board of Trade will cause a complete investigktion of the whole question to be made at an early date, so that analysts may reach finality in their inferences from butter analysis. I have only one word more to add, it is in connection with Mr. Allen's apparent wish to show that the specific gravity of B and 0 are normal. This is effected by finding fault with our old friend Westphal, which instrument,, since I first introduced it for ascertaining the specific gravity of liquids at high tem- peratures, has been of great value to the analyst. Mr. Allen should have given figures for, say, beef-fat taken under the same con- dition as butters B and 0, using the faulby division eight, of the Westphal.I give them below, so that it may be seen that there is a good margin by the gravity process between butter-fat and ordinary fat, viz- Butter 0, specific gravity at 212" . . . . 8663 Beef-fat, specific gravity a t 2 1 2 O . . . . 859.6 Lt would also have been most valuable information if Mr. Allen could have given the gravities of beef-fat and butter-fat by the specific gritvity bottle used by Professor Stein. One word more regarding the Reichart method, which has always met with such favour a t the hands of Mr. Allen, and which I am informed is the one almost, if not exclusively, relied upon by Professor Stein for his daily examination of butter. I desire to csll attention to the paper by Dr. Wollny in the January and February numbers of the ANALYST for 1888. I n page nine, experiment 135, Dr. Wollny gets20*45c.c., as the Reichart of a genuine butter. On page ten, the explanation of this extraordinary resuit is given, and this explanation together with the possible sources of error (one possible error is, we may get minus 30 per cent. from cohesion of fatty acids) which Dr. Wollny points out upon page forty, would be sufficient to cause us even now considerable doubt as to the reliability of the process. I n conclusion, the inference, I think, which may fairly be drawn from the fore- going remarks is that the specific gravity method either of Dr. Bell or myself, and the Angell-Hehner insoluble and soluble fatty acid determination, as modified by Dr. Muter and others, are still the most reliable methods for determining the genuineness of butter, I do not assert it was so committed." Y Y -0 + 00 00 PD " Y Y 0 u Y >a Y h Y _. . . . . . . . . c3 a z w s 0 u 0 0 * * . . . . . . . . . . . . Insol. Fatty Acids. Sol. Fatty Acids. Reichw t . Specific Gravity. Insol. Fatty Acids. Sol, Fatty Acids. -~ Reicbart. Specific Gravity. Insol. Fat t.y Acids. Sol, Fatty Acids. Reichart.

ISSN:0003-2654    

DOI:10.1039/AN8891400051

出版商:RSC    

年代:1889

数据来源: RSC

摘要:

THE ANALYST. 57 ON SOURCES OF ERROR IN DETERMINATION OF NITROGEN BY SODA- LIME, AND MEANS FOR AVOIDING THEN. BY W . 0. ATWATER. (Continzced from page 10.) Previous experience had persuaded us that when (1) the tubes are of moderate length and compactly filled with soda-lime, (2) only a moderately high heat is used, (3) the combustion does not proceed too slowly, and (4) the flames are turned off and the tube allowed to cool slightly before aspirating with air, there is no considerable loss of nitrogen by either dissociation or oxidation. I n the fir& seriep, in which the operation was conducted in the usual way, a confirmat.ion of this impression was sought. I n the second series the effect of increasing the length of the tube and with it the time of sojoiirn of the ammonia gas in the tubes, without increasing the heat, was observed.In the third series the effect of high heat was tested by using long tubes as in the second series, and making the heat much greater. I n the fourth series it was sought to learn whether the loss of nitrogen observed in the third series was due to dissociation or oxidation or to both. The trials of the fifth series had a similar object. The results are given in detail in Table II., which includes all the deter minations made, and are recapitdated in Table 111. The figures of the first series indicate that with tubes of our ordinary length, 40 cm. or a little less, compactly filled (about 16 cm. with mixture of fine soda-lime and substance, 4 cm. with “ rinsings ” of fine soda-lime, and 12 cm. with an anterior layer of coarse soda-lime), at aheat sufficient t o make the tube dull red, designated here as “medium,” and with aspiration by air after the tubes had begun to cool, there was no l o ~ s of nitrogen.I n the second series the tubes were long enough to make the anterior layer of coarse soda-lime about 35-40 cm.; the charging otherwise was the same as in the first series. Lengthening the tube had no effect upon the result. At moderate heat there was no loss by diesociation with closely- TABLE 111. Hecapitulation of Determinations of Nitrogen in Ammonium SuZphate under Diferent Conditions. Five series of trials were made. The percentage of nitrogen obtained was the same. 1st 2nd 3rd 4th 5th and Anterior Usual.* Very long.? Very long.? Very long.? Very kmg..f.1 Per cent. 0.03 0.01 0.06 0.2 1 0.03 Heat of Com- bustion. Medium. Medium. Hjgh. High. Medium. Nitrogen found. Aspirated with. Air. Air. Air.: Hydrogen. Hydrogen. Pel- cent. 21.12 21.12 20.83 20.83 21.11 Loss of Nitrogen in per cent. of total Nitrogen. Maxim’m. Per cent. .. .. 1-5 2.0 . . Average. Par cent .. . . 1.4 1.4 .. packed tubes, even when the latter were very long and the exposure of the ammonia to t h e heat was increased. * Tube about 40 c.m., anterior layer of soda-lime about 12 c.m. t Tube 76 cm., anterior layer about 35-40 cam. $ In one case with carbonic acid.58 THE ANALYST. In the third series the conditions were the same as in the second, except that the temperature was made as high as the tubes of the most difficultly fusible Bohemian glass we could obtain would endure without bursting.The standard acid employed was rather concentrated, so that but a small quantity was needed in the nitrogen bulb, and the internal pressure was thus reduced to a minimum. It was thus possible to heat the tubes to bright redness without their bulging. Instead of 21.12, only 20.83 per cent. of nitrogen was obtained. This falls short of the actual amount by 0.29 per cent. of the weight of the sulphate of ammonia, or 1.4 per cent. of the total nitrogen. The indica- tion of loss by either decomposition or oxidation of ammonia was very apparent. I n the fourth series the conditions were the same a s in the third, except that air was excluded, the object being to find, if practicable, how much of the loss in the previous series was due to the burning of ammonia by the oxygen of the air, and how much to dissociation. I n No.10, the length of the tube was actually 80 cm. instead of 75 cm. as in the other cases. The extra 5 cm. of the posterior end were filled with bicarbonate of soda, which was heated at the beginning of the experi- ment to expel the air present in the tube, and again a t the end to drive out the residual ammonia. I n Nos. 11 to 14, as in all of the next series, in which hydrogen was used for the same purpose, the tubes were about 80 cm. long or a little longer, the extra 5 cm. at the posterior end being filled with asbestos. The hydrogen, which had been dried by sulphuric acid, was passed through the combustion tube for three quarters of an hour, and the tube was then exhausted by a mercury pump, after which hydrogen was again passed through for half an hour.Assuming that the air had thus been very nearly all removed, the combustion was conducted a t the very high heat, as in the third series. When it was done, hydrogen was again passed through to wash out the residual gases, pre- cautions being taken to admit no air. The amount of nitrogen obtained averaged the same as in the third series, 20.83 per cent, The exclusion of air made then no difference in the result. This indicated that the loss was due not to oxidation, but to dissociation of ammonia. It is observable, furthermore, that the individual results in the third and fourth series vary considerably, the range in the fourth series being 9 1 , while in the first and second series it was only *03 per cent.While the agreement of duplicates is a very UD- certain evidence of the correctness of an analysis, a wide disagreement may be regarded as a tolerably sure indication of error. In the fifth series the conditions were the same as in the fourth, except that the combustion was made a t ‘‘ medium’’ heat, The results, which average 21.11 per cent., are practically identical with each other and with those of the first and second series. The difference in condition between this and the fourth serieP, like that between the second and third, is simply one of heat, and that difference in each case evidently makes the whole of the difference in result. To resume :-In every case in which the medium heat was employed, whether with long or with short tuhee, whether with or without air, the full amount of nitrogen was obtained.I n every case with the high heat there was a loss from 1 t o 2 per cent. of the total nitrogen in the substance. Neither the length of the tubes nor the presence or absence of air made any differenca in either the amount of nitrogen obtained or the uni- formity of the results, but the high heat materially reduced the amount of nitrogen and made wide variations in results of duplicate determinations. That more definite statements as to temperature at which the dissociation takes place are to be desired, goes without saying. Ramsay and Young,* in a series of very interesting experiments on the temperature of dissociation of ammonia, find that the point at which it commences varies greatly with the nature of the surrounding medium.* Jourr. Cllem. SOC., 1884, Proc. p. 88.THE ANALYST. 59 In a porcelain tube filled with broken pieces of porcelain, in an iron tube filled with porcelain, and in a glass tube filled with ignited 'I porous " asbestos cardboard, to expose the gas to a large surface, the decomposition commenced at about 500" or below. At 50Oo-52O0, however, it was very small, but increased gradually a t higher temperatures. In contact with a glass surface the temperature at which decomposition begins was much higher. The nature of the surface heated has a very great influence on the amount of ammonia decomposed. In a plain dry iron tuba the decomposition was apparently com- plete at 7808, but if water was present only 95 per cent. was decomposed. At 760°, in a glass tube containing iron wire, 64.3-76 per cent. of the ammonia was decomposed; but when copper was substituted (the other conditions remaining essentially unaltered) only 2.0 per cent. was decomposed. The authors find that '( the amount of decomposition depends partly upon the rate of passage of the gas, or, in other words, on the time of ex- posureto heat," and that " the extent of surfacealso influences the amount of decomposition. (To be continued.)

ISSN:0003-2654    

DOI:10.1039/AN8891400057

出版商:RSC    

年代:1889

数据来源: RSC

摘要:

THE ANALYST. 59 - LAW NOTES. HEAVY PENALTY FOR ADULTERATED MILK.-At Wolverhampton Police Court on January 30th, before Mr. Neville (stipendiary)-I?. W. Vickers, Tissington, Ashbourne, Derbyshire, was charged with selling adulterated milk.-Mr. Brevitt (town clerk) prosecuted, and said that the dsculty the prose- cution had had in this case was to secure the person who, under the Act, was really liable for the alleged adulteration, and, if the defendant were convicted, he must ask for a substantial penalty.- Inspector Blanton deposed that on January 2nd, from information received, he went to the London and North-Western Railway station at Wolverhampton, and saw a churn of milk containing twelve gallons. It bore a warranty label, and was consigned from Ashbourne to the Midland Dairy Company, Horseley Fields.Witness took a sample from the churn, and had it analysed by Mr. E. W. T. Jones, the borough analyst, who certified that it contained 19 per cent. of water.-Mr. Paine, for the defence, urged that the defendant had received no notice from the prosecution of their intention to test the milk, nor had he received a sample from them.-The Stipendiary said he thought it would be fairer to the defendant in future if a sample were supplied to him after it bad been taken by the prosecution, although tluwe was m legal obligation upon them to do so. It was satisfactory that the original vendor of the milk had been found and proceeded against. I n justice to the milksellers in the town, he must impose the full penalty under the Act-namely, $20, and costs.ADULTERATED PEPPER.-& Glasgow Sheriff Court on the 14th ult. Matthew Kerr, grocer and rovision merchant, 61~, King Street, Calton, was charged before Sheriff Balfour, at the instance of b r. Peter Fyfe, sanitary inspector, with having, on 19th December, sold to Mr. Robert Inglis, assistant sanitary inspector, a quarter pound of black pepper, which on analysis was found to contain 3 per cent. of sand, 4 per cent. 01 mineral matter, and 7 per cent. of pepper husk, all of which are extraneous to whole pepper. The respondent pleaded guilty. His agent, Mr. Wm. Shaw, writer, stated that Mr. Kerr bought the pepper from a house in Glasgow which held a guarantee from a Liverpool house that the pepper was pure. It was what was known as Penang pepper, which had naturally a large amount of impurity in it.After hearing a further statement from Mr. Shaw, Mr. R. G. Ross, writer, who pro- secuted, and Dr. Tatlock, the analyst, his Lordship gave judgment. The Sheriff said that he thought Nr. Kerr had been well advised in tendering a plea of guilty. I t appeared that black pepper had got a core and an outside husk, and in preparing it for the market there must be to a greater or a lesser extent a certain quantity of sand and mineral matter adhering to the pepper. Dr. Tatlock had taken the Somerset House standard, which allowed a percentage of 3) of sand, and in regard to mineral matter he had been guided by public analysts and writers of authority, who allowed 7 per cent. for mineral matters, and as long as the percentage of sand and mineral matter only came to 3) and 7, no prosecution would be directed against any party who sold black pepper.But the line must be drawn somewhere. From the manner in which this black pepper was prepared, it was perfectly clear that the pepper berries, after being dried, must have particles of earthy matter adhering to the husks, and if black pepper were sent over to this country with an immense proportion of earthy matter adhering t o the husks, with the intention of being sold in that way, it would not do to allow such a sale to take place, because the earthy mattter might get in, not by fair, but by foul means. To prevent that the Somerset House and those public analysts and writers of authority had fixed what he presumed were reasonable and fair standards. Dr. Tatlock had acted most liberally in stating the adulteration, because, in point of fact, the mineral matter really amounted to about 16 per cent., and the sand to about 6 per cent. It was not to be supposed that in inflicting a ligbt penalty, as he was going to do, he by any means countenanced black pepper being sold in the state in which Mr. Kerr had sold it. Eut he had no reason to doubt Hr. Kerr’s boitajd8s in the matter. He apparently bought from a wholesale house, who, on their part, held a written guarantee from the foreign sellers. Mr. Kerr, unfortunately, had not been armsd with such a written guarantee, and he was therefore liable to the authorities for selling the adulterated article. As it was the first case of the kind that had been brought before him, the Sheriff, in the circumstances, inflicted a penalty of 16s. The fine wae paid.

ISSN:0003-2654    

DOI:10.1039/AN8891400059

出版商:RSC    

年代:1889

数据来源: RSC

摘要:

60 THE ANALYST. CORRESPONDENCE. [me .Editor is rttot in any way responsible for opkions expressed by his correspondents.] To the Editor ofthe ANALYST. SIR,-AS few penalties for aduiteration are inflicted, the enclosed report* may interest your readers, especially as the case comes under the special provision of the Act for procuring milk for analysis a t the railway station, or in course of delivery. The following are the analytical results of this sample of milk:- Specific Gravity at 60” 3’. . . . . . . . . . . . . . . . 1025.7 Total golids . . . . . . . . . . . . 9.93 per cent. Fat (by Adams’ Cbil mlihodj . . . . . . . . . . . . . . 3.03 ,, Solids not Fat (by difference) . . . . . . . . . . . . 6-90 ,, ,, ,) (by Bell’s method) . . . . . . . . . . . . 7.29 ,, Ash . . .. . . . . . . . . . . . . . . . . . . . . 0.63 ,, Lactose (C, ,H, *01 by Polariscope . . . . . . . . . 3.60 ,, - - - 9 9 ,) by Fellling . . . . . . . . . . . . 3.54 ,, - Yours truly, E. W. T. JONES, Publio Analyst for Staffordshire, etc, A MARE’S NEST. SIB,--NOW that the Society of Public Analysts have appointed a SeZect Committee (which for brevity’s sake we shall term the A B C of the Society) to investigate the subject of Butter Analysis owing to the supposed alarming state of matters brought about by Mr. Allen’s late paper, entitled ‘‘ Abnormal Samples of Butter,” it may be of interest to the members of the A B C to know that as far back as the year 1884, Professor Wiley of Washington, i n analysing nine samples of genuine butter found as a minimum for insoluble fatty acids 88’50, and a maximum of 89-89 per cent., the first figure being Angel1 and Hehner’s highest figure.In the year 1886, Professor E. Waller, of New Pork, found 90.26 per cent. as a maximum, and 86a40 as a minimum for twenty-six genuine butters examined by him ; and in the same year Professor C. B. Cochrin found 87.7 per cent. as his highest figure, and 86.7 as his lowest figure in twenty-five genuine Pennsylvania butters, figures which prove conclusively that it is not only in Danish Butters that high percentages of insoluble fatty acids are to be found. The figure 89.89 is as near as a toucher to 90 per cent. (and we all know what as near as a toucher means), a figure obtained in the year 1884, the difference between 89.89 and 90 being less than the difference between the figures obtained by Mr.Bllen in his two analyses which were performed in duplicate, and by a strange coincidence Professor Waller’s highest figure 90.24 obtained in 1886 coincides with one of Mr, Allen’s estimations, Is it possible that the A B C are ignorant of these facts ?-Yours, etc., THE GBEAT I AM. TO CORRESPONDENT$, F. A. B.-Had you applied some years ago you might possibly have gained admittance without exam- ination, but, so far as we know, such days are now over. We are not aware that there is any relaxation of the rule as to the fixed course of atudy, and, moreover, we fear that, even if there were, the exam- ination itself would present an insuperable barrier to a man in business who had not time to go through a special course. That this should be so is only just, because it is intended t o exclude all but those who really make an actual profession of chemistry as distinct from pharmacy. Undoubtedly some phar- macists have managed to get in at present, but, as they die off, their places are not likely to be fllled up by others of the same status, because a man who became a practising consulting chemist would naturally drop the shop altogethel‘, it being impossible t o combine the two businesses, which are totally distinct in every respect, PROF. I(INNICUTT.-htter to hand but no paper arrived yet (February 25th). When it comes will make use of it as soon as possible. Communications on Literary or Eschange Matters to be sent to 325, Kennington Road, London, S.E. * &e Law Notes.

ISSN:0003-2654    

DOI:10.1039/AN8891400060

出版商:RSC    

年代:1889

数据来源: RSC